Ingestible devices such as capsules known in the art may have an in vivo sensing system, such as an in vivo camera system or other sensing systems such as temperature sensors or pH sensors. An encapsulated in-vivo video camera system may capture and transmit images of the gastrointestinal (GI) tract while it passes through the GI lumen. The system may include a capsule that can pass through the entire digestive tract and operate as an autonomous video endoscope.
FIG. 1 shows an exemplary prior art ingestible device 10 within a human body 12. Device 10 has an imaging device 14, which transmits in vivo images to a set of antennas 16 within an antenna belt 17 surrounding a portion of body 12. Device 10 may, for example, take the form of a capsule, but may take other suitable shapes or forms.
Device 10 has power sources such as batteries 18 which provide power to the various elements of device 10. However, batteries may add weight to the device and may have a limited capacity.
Some endoscopic devices have no batteries. Energy may be provided to these devices by for example transmitting an electromagnetic field at a patient's body in which such a device is inserted. The device may include an element that can receive and convert the transmitted waves to electric power.
Typically, a device is an autonomously moving unit where the medium present between the electromagnetic waves receiving unit in the device and the external electromagnetic field may be non-homogenous due to the presence of obstructions or different materials, for example bone, muscle, fat, and tumors. Other material may be present between the receiving unit and the external field. A patient may be placed in an electromagnetic field generating cage and the relevant section of the patient's body may be irradiated by an electromagnetic field in order to ensure that electromagnetic waves reach a device within the patient's body even if obstructions, such as described above, are present. Thus, there exists a need for a more efficient method of providing energy to an in vivo device.